Officials carry the flaperon which washed up on Reunion Island last month

Speaking to the Malaysian Bernama news agency, Rahman said: "I believe that when the aircraft went out of fuel, it glided downwards and landed on the water with a soft impact ... that's why I believe the plane is still largely intact."

Rahman added: “It [the flaperon] was only slightly damaged and was just encrusted with barnacles. Its appearance indicates that it was not violently torn from the aircraft’s main body… it does seem that it got detached pretty nicely at its edges.

“If MH370 had crashed with a really hard impact, we would have seen small pieces of debris floating on the sea immediately after that.

“Furthermore the flaperon that was recovered wouldn’t have been in one piece… we would have only seen bits and pieces of it.”

The debris washed up on the shore of Reunion Island, which is off the coast of Madagascar

The theory raises the intriguing possibility that one or more of the 239 people on board were alive when the aircraft ditched in the ocean after flying more than seven hours off course.

Intact landings on water are possible – as evinced by the US Airways flight 1549 which made an emergency landing on the Hudson River in 2009.

The Sydney Morning Herald points out the only stories Bernama usually publishes are those sanctioned by the government in Kuala Lumpur.

Wilson says the most likely scenario is that Captain Zaharie Shah deliberately depressurised the cabin, thereby depriving those on board of oxygen and causing them to lose consciousness before the Boeing 777 disappeared beneath the waves.

Although oxygen masks would have dropped down automatically from above the seats, the available supply was limited to just 20 minutes.

Those unable to grab a mask, including sleeping passengers, would have passed out within the space of a few minutes.

The entire 'ghost plane', including her cabin crew whose air supply is only marginally longer, would have slipped into a coma and died shortly after from hypoxia.

Shah, who locked his co-pilot out of the cockpit, survived long enough - either by re-pressurising the aircraft, or from breathing his own, more extensive air supply - to evade radar and "execute his master plan", Wilson and his co author Geoff Taylor conclude.

They say he then performed a controlled ditching in the sea, sinking the plane in one piece, which explains why so little debris has been found.